So, I'm told that electron microscopy provides greater resolution than traditional photo/optical (i.e. visible light) microscopy, due to the (ahem) "fact" that "electrons are physically smaller than photons".. Which I'm pretty sure is not necessarily true, (or static/constant). But by the same token, I am not a physicist..
The analogy that I'm presented with is that in this context, the size (and density) of photons and/or electrons are supposedly comparable to pixels (and ppi/dpi) of an LCD monitor, CCD image sensor, raster image, etc.
So, it sounds plausible, and it's a nice, relatable explanation for the common man. But is it factual?
If not, what's really going on here?
Best Answer
Here is a basic overview- experts are invited to add detail.
Subatomic particles like electrons actually possess a wavelength that is related to their energy, even though they behave most of the time like tiny point particles and not like waves. By accelerating a beam of electrons to very high energies, their wavelengths become far shorter than that of a photon of visible light, and this allows them to resolve objects far smaller than that which can be seen with focused beams of visible light.
In a typical electron microscope, the electron beam tube in which the acceleration occurs is about three to four feet long, but this principle can be scaled up to resolve the interior of a single proton. In this case, the beam tube needs to be more than ten thousand feet long; the SLAC particle accelerator in California has one of these 2.2 miles long which was used to detect the interior structure of protons in the late 1960's.